Selector valve



Dec. 9, 1952 R, B, CAMPBELL 2,621,050

SELECTOR VALVE:

Filed Feb. 2, 1946 2 Sl-IEETS-Sl-IEET l ,4 fr0/Mfrs Dec- 9, 1952 R. B. CAMPBELL 2,621,050

SELECTOR VALVE Filed Feb. 2, 1946 2 SHEETS--SHEET 2 [VVE/V729@ @o0/Vey 5. CAMPELL HAR/Q5, A//Ec/f F05 TER E HAR/ws Patented Dec. 9, 1952 asm* orties SELECTOR VALVE Application February 2, 1946, Serial No. 645,199

2 Claims. l

My invention relates generally to Valves and, more specifically, to selector valves which may be employed for controlling the distribution of fluids, a primary object of my invention ybeing the provision of a selector valve which is adapted for reversing the direction of iiow of a uid. A selector valve of this general character may be incorporated in any installation wherein -flow re'- versals are required, and is particularly adapted for employment in hydraulic systems to control the direction oi motion of various hydraulicallyactuated, reversible members such as pistons, for example.

In general, my selector valve includes a valve body having an inlet passage therein which may be connected to a fluid 'supply source, and having an outlet passage therein for expended fluid, the valve body also being provided with a pair of auxiliary passages which may be connected to i any desired installation to 'supply fluid thereto and to return expended fluid therefrom. Another object of my invention is 'the provision of a selector valve including 'means for reversing the direction of flow through 'the aforesaid 'auxiliary passages whereby either 'auxiliary passage may be employed for lsupply-ing -fluid to therdesired installa-tion, of for returning expended uid therefrom. n

The valve body is preferably provided with a pair of valve chambers having means therein for controlling the direction of flow through the auxiliary passages, the inlet and 4outlet passages communicating with both valve chambers and each auxiliary passage communicating with only one of the valve chambers. The selector valve is provided with a valve member in each Valve chamber, a further object of my invention being the provision of valve members each of which is adapted to provide iluid communication between the inlet passage and either auxiliary passage, and between either auxiliary passage and the outlet passage.

An important object of my invention is the provision oi actuating vmeans for moving the valve members in 'the valve chambers into either a neutral position, oi' into one of a pair oi operating positions in which 4now through the auxiliary passages is in opposite directions. More spe-eincally, an object 'of my invention is to provide operating positions in each of which one of the valve members provides communication between the inlet passage and one Vof the auxiliary passages, and in ea'ch of which the other valve member provides communication between the other auxiliary passage and the outlet passage,

Still another object is to provide means for releasably securing vthe actuating means in the neutral position to indicate the neutral position of the valve members to an 'operator of the selector valve.

An additional object of my invention is 'the provision of actuating means including eccentric means for moving 'the valve members and for maintaining the desired relationship therebetween.

A-n important object is 'the provision of a valve wherein rubber-like sealing I elements may be employed to provide a seal between the valve member and the walls of the valve chamber and may be slidably moved past ports lin the walls of the valve chamber without damage.

Still another object is the provision oi a valve wherein the valve members are hydraulically balanced by iiuid in the valve chambers.

The foregoing objects and `advantages of my invention, together withuvarious other objects and advantages which will be apparent hereinafter, may be realized by means "of the embodiment which is illustrated in the accompanying drawings and is described -in detail hereinafter. Referring to the drawings, which are intended as lustrative only;

Fig. 1 is an v'elevational view of fa selector valve which embodies the fundamental principles of my invention;

Fig. 2 is an enlarged 'sectional View thereof which is taken along the broken line 2&2 of Fig. l and which illustrates vone operati-ng position `of one valve member;

Fig. 3 is a view which is similar to Fig. 2J but which illustrates another operating position 'of the valve member shown therein;

Fig. 4 is an enlarged, fragmentary sectional view which is taken along the' broken line "4-25 of Fig. 1 and which illustrates the operating position of another valve member which 'corresponds to the operating .position of the valve member shown in Fig. 2;

Figs. 5 and 6 are enlarged sectional views 'which are taken along the breken lines '545 and '645, respectively, of Fig. l; kand Figs. '7, 8, and 9 are further enlarged, fragmentary sectional views which illustrate the-operation of a sealing element.

Referring to the drawings, the selector valve includes a valve body l0 having a pair of valve chambers ll and IYZthe'rein which are preferably cylindrical and arebe'st shown in Figs. 2 and 4,

respectively, the valve body being provided with an inlet passage 7I3 'therein which communicates with both valve chambers, and being provided with an outlet passage I4 therein which also communicates with both valve chambers. The valve body I is also provided with a pair of auxiliary passages I and I6 therein which communicate with the valve chambers I I and I2, respectively.

Valve members I9 and 29 are slidably disposed in the valve chambers II and I2, respectively, as best shown in Figs. 2 and 4, respectively. The valve member I9 is provided with passages 2I and 22, the passage 2| being adapted to provide communication between the inlet passage I3 and the auxiliary passage I5 to permit flow out of the auxiliary passage I5 as indicated by the arrows 23 in Fig. 3, and the passage 22 being adapted to provide communication between the auxiliary passage I5 and the outlet passage I4 to permit flow into the auxiliary passage I5 and out of the outlet passage asindicated by the arrows 24 in Fig. 2. Similarly, the valve member is provided with passages which are adapted to permit ow either into the inlet passage I3 and out of the auxiliary passage I6, or into the auxiliary passage I 6 and out of the outlet passage I4. Since the valve member 23 and the aforesaid passages thereof are identical to the valve member I9 and the passages 2I and 22 thereof, the details of the valve member 23 are not shown in the drawings.

The selector valve includes actuating means 21 for moving the valve members I9 and 29 into either a neutral position or into one of a pair of operating positions. In one operating position, the valve member I9 provides communication between the inlet passage I3 and the auxiliary passage I5 as indicated by the arrows 23 in Fig. 3, and the valve member 2U provides communication between the auxiliary passage I6 and the outlet passage I4 in a manner which is not specically shown but which is substantially the same as the manner in which the valve member I9 provides communication between the auxiliary passage I5 and the outlet passage as indicated by the arrows 24 in Fig. 2, the valve member 23 being in a position which is shown partially in Fig. 4. In the other operating position, the valve member I9 provides communication between the auxiliary passage I5 and the outlet passage I4 as indicated by the arrows 24 in Fig. 2, and the valve member 23 provides communication between the inlet passage I3 and the auxiliary passage I3 in a manner which is not specifically shown in the drawing but which is substantially identical to the manner in which the valve member I9 provides communication between the inlet passage and the auxiliary passage I5 as indicated by the arrows 23 in Fig. 3. Thus, it will be apparent that in the operating position shown in Fig. 2, uid flows from the inlet passage I3 to the auxiliary passage I6, and from the auxiliary I5 to the outlet passage I4, whereas in the operating position shown in Fig. 3, fluid flows from the inlet passage to the auxiliary passage I5, and from the auxiliary passage I6 to the outlet passage. Thus, in the operating position shown in Fig. 2, the auxiliary passage I6 may serve as a supply passage for a desired installation and the auxiliary passage I5 may serve as a return passage for expended fluid, whereas in the operating position shown in Fig. 3, the auxiliary passage I5 serves as the supply passage and the auxiliary passage I6 serves as the return passage.

When the valve members I9 and 23 are in the neutral position, communication between the inlet passage I3 and the auxiliary passages I5 thereforer be .described simultaneously.

and I5 and between the auxiliary passages and the outlet passage I4 is prevented so that no flow occurs. In order to provide an operator of the selector valve with positive means for determining the neutral position, I prefer to provide means 28 for releasably securing the actuating means 21 in the neutral position to provide the operator of the selector valve with the desired feel for the neutral position.

For certain applications of my invention which will be described in detail hereinafter, I prefer to provide the selector valve with pressure regulating means 29, as best shown in Figs. 2 and 3, to prevent the development of excessive fluid pressures in the auxiliary passages I5 and I6 because of thermal expansion of the fluid therein when the valve members I9 and 29 are in the neutral position.

Considering the selector valve in more detail, the valve body I0 is provided with a pair of longitudinal bores 3l and 32 therein as shown in Figs. 2 and 4, respectively, or as best shown in Fig. 6. The bores 3I and 32 are provided with identical tubular liners 33 and 34 therein, respectively, which define the cylindrical valve chambers I I and I2, respectively, only the liner 33 be ing shown completely since the two are identical. Consequently, the two liners 33 and 34 and the structure associated therewith will be described simultaneously.

The liners 33 and 34 include annular iianges 33 which are seated in recesses 31 in the valve body I0, the valve chambers II and I2 being enclosed by flanged caps 38 which receive an end of each of the liners. The liners 33 and 34 and the anged caps 38 may be secured to the valve body ID by screws 39 or the like, as shown in Fig. 1, which extend through the flanges 33 on the liners. The liners 33 and 34 are provided with a plurality of annular grooves 4I therein having annular sealing elements 42 therein to provide a fluid-tight seal between the liners and the valve body I0, the sealing elements preferably being formed of a material such as rubber or the like.

The inlet passage I3 includes a threaded bore 43 for a suitable inlet fitting (not shown), and includes a transverse bore 44 which communicates with an annular groove 45 in each of the liners 33 and 34. The liners 33 and 34 are provided with a plurality of ports 46 therein which provide communication between the annular grooves 45 and the valve chambers II and I2.

The outlet passage I4 is similar to the inlet passage I3 and includes a threaded bore 48 for a suitable outlet fitting (not shown) as best shown in Fig. 5. The outlet passage I4 includes a transverse bore 49 which provides communication between the longitudinal bores 3| and 32 and hence between the valve chambers II and I2 as best shown in Figs. 2 and 4.

The auxiliary passage I5 includes a threaded bore 50 in the valve body I0 which communicates with an annular groove 5I in the liner 33, the auxiliary passage I5 also including ports 52 and 53 which extend through the liner 33 into the valve chamber II. The auxiliary passage I6 is identical to the auxiliary passage I5, except that it communicates with the valve chamber I2 instead of the valve chamber II, and is not shown completely.

With one exception which will be described in detail hereinafter, the structures of the valve members I9 and 20 are identical, the valve member 29 not being shown completely, and will, The

valve members I9 and 20 are piston-shaped and are preferably formed in two sections and 57 which are suitably secured together for convenience of manufacture, each section 5@ being provided with a bore 5B therein which receives a complementary portion 59 of the corresponding section 5?. Each of the valve members le and is provided with annula;` grooves iii therein for annular sealing elements t? of a material such as rubber or the like to provide a fluidtight seal between the valve members i9 and and the liners 33 and 3ft, respectively. Each of the liners 33 and 3Q is also provided with an annular groove 63 therein for a rubber-like sealing element 64 to provide a fluid-tight seal between the ports and 52 in the liners when the valve members l and 28 are in operating posi-tions such as those illustrated by the valve member IS in either Fig. 2 or Fig. 3, the annular sealing elements 64 being adapted to provide a seal between the ports 4S and 52 through the liners in a manner which will be described in detail hereinafter in connection with Figs. 7 to 9, inclusive.

The passage 2l through the valve member i9 includes an annular groove @t therein which is adapted to communicate with the ports d6 through the liner 33 when the valve member IS is in the operating position shown in Fig. 3, the passage 2i including openings 6l which communicate with the annular groove 66 to admit fluid into the bore 58 in the valve member i9. The passage 2i also includes ports 58 which are adapted to register with the ports E2 in the liner S3 to permit uid to ow into the auxiliary passage l5 when the valve member i9 is in the position shown in Fig. o. rihe valve member 2E is provided with a passage therethrough which is identical Ito the passage 2i but which is adapted to provide communication between the inlet passage I3 and the auxiliary passage it instead of the auxiliary passage i5.

The passage Z2 of the valve member i9 provides uid communication between the auxiliary port l5 and the outiet port lli when the valve member I9 is in the position shown in Fig. 2, the passage 22 being defined by one end of the valve member li? and portions of the wall of the valve chamber li thereadjacent. The valve member 2i) is provided with a passage which is identical to the passage 22 except that it is adapted to provide communication between the auxiliary port I5 and the outlet port l 5 when the valve member 2i) is in an operating position correspending to the operating position of the valve member I9 which is shown in Fig, 2.

The valve member is includes a bifurcated actuating element iii having branches or arms il, as shown in Fig. 2, and the valve member 29 includes an actuating element l2 having branches or arms 13, as shown in Fig. 4, the only structural difference between the valve members i9 and 2i! being that the arms 'El and 13 of the actuating elements 'eil and 'i2 extend in opposite directions, In all other respects, the structures of the valve members it and 2i? are identical as mentioned previously.

As best shown in Figs. 5 and 6, the actuating means 2'! includes a rotatable actuating member or shaft i5 which is disposed in a ltransverse bore 'i in the valve body EQ, the transverse bore l5 being perpendicular to the valve chambers E l and i2. The shaft 'i5 is journaled in bearings 'il which may be bolted or otherwise secured to the valve body I0, each of the bearings being prolli) vided with an `annular groove 78 therein for an annular 4sea-ling element 'I9 of rubber or the like to provide a huid-tight seal between the bearings and the valve body. The shaft ,'15 is provided -with an annular groove 55) therein for lan annular sealing element 8i to seal the shaft `with respect to one of the bearings 11, the shaft being enclosed by the other bearing.

The shaft T5 is formed with two enlarged portions 83 and 84 having transverse slots 85 and 86 therein, respectively, which receive the actuating elements 'lil and l2 therein, respectively. As best shown in Figs. 2, 3, and 5., an eccentric element 83 extends across the slot 85 and is disposed between =the branches 'H of the actuating element 19, the eccentric element being suitably secured to the enlarged portion 83 of the shaft l5. Another eccentric element '89 is disposed diametrically opposite the eccentric element `88, the eccentric element 8! extending across the `slot 86 and being disposed between the branches "I3 of the actuating element l2 as best shown :in Fig. 4. As the shaft 15 vis rotated by any suitable mechanism (not shown) which may be connected to an end portion 9E) thereof, the eccentric elements 88 and 8S act through the actuating elements TB and 'il respectively, to 'reciprocatethe valve members I9 and 2G, respectively, in the valve chambers i and i2. Thus, the valve member I9 Vmay be displaced from the operating position shown in Fig. 3 through the neutral position and into the operating position shown in Fig. 2 by rotating the shaft 75 in a clockwise direc-tion as viewed in Figs. 2 and 3. Such rotation simultaneously displaces the valve member 23 from an operating position corresponding to that shown in Fig. 2 through the neutral position and into an operating position corresponding to that shown in Fig. 3 because of the relative positions of the actuating elements 10 and 12 and eccentric elements 88 and 89 as previously described.

Thus, when the shaft 'l5 is in a position such that the eccentric elements 88 and 83 assume the positions shown in Figs. 2 and 4, respectively, the valve member I9 provides fluid communication between the auxiliary passage l5 and the outlet passage M through the passage 22, as indicated by the arrows 2d, and the valve member 2i! provides iluid communication between the inlet passage I3 and auxiliary passage I5 through the aforesaid passage thereof which corresponds to the passage 2| of the valve member I9. Similarly, when the shaft l5 is in a position such that the eccentric element 8S assumes the position shown in Fig. 3 and the eccentric element 89 assumes a corresponding position (not shown) the valve member I9 provides fluid communication between the inlet passage I3 and auxiliary passage l5 through the passage 2i, as indicated by the arrows 23, and the valve member 29 provides fluid communication between the auxiliary passage I6 and the outlet passage i4 through the aforesaid passage thereof which corresponds to the passage 22 of the valve member l 9. The two operating positions are positively defined in view of the fact that the travel of the actuating elements 1U and 'i2 is limited by the end walls of the bores 3| and 32 respectively, and by adjacent ends of the liners 33 and 34, respectively, as will be apparent from Figs. 2, 3, and a.

In order to define the neutral position of the valve members I9 and 20, the neutral position being substantially midway between the two operating positions, and to provide the operator of the selector valve with a positive feel for the neutral position. I prefer to provide the means 28 for releasably securing the actuating means 2T in the neutral position. As best shown in Fig. 6, the shaft I5 is provided with a transverse bore 93 therein for a detent 94 having a tapered nose 95 which extends into a notch 96 in one of the bearings 'I'I when the shaft, and consequently the valve members I9 and 20, are in the neutral position, the detent being urged into the notch by a compression spring 91 which is seated in a bore 98 in the detent and is retained by a pin 89. The detent 94 is provided with a bleed opening |00 therethrough to provide equal fluid pressures on either end thereof so that the detent will operate in the same manner regardless of the pressure of the fluid thereadjacent.

Although my selector valve may be employed for performing various functions, the valve may be used particularly advantageously for actuating a double-acting piston (not shown) which may be employed for extending and retracting the landing gear (not shown) of an airplane, for example. By connecting the auxiliary passages I5 and I3 to opposite sides of such a piston, the flow of fluid to and from the piston may be reversed as desired to produce movement of the piston in either direction, since, in one operating position, fluid flows from the auxiliary port I5 and into the auxiliary port I6, and, in the other operating position, the flow is in the opposite direction. However, the selector valve may be employed for performing various other functions and I do not intend to be limited to the particular function described.

In many applications of the selector valve, it may be necessary to compensate for possible pressure increases due to thermal expansion of the fluid in the auxiliary ports I5 or I5 when the valve is in the neutral position for any length of timey this being particularly true of the doubleacting piston installation described in the preceding paragraph wherein the valve may be operated at only infrequent intervals. The pressure regulating means 29 are adapted to release i fluid from the auxiliary passages I5 and I6 to compensate for such pressure increases and are disposed in bores |02 in the valve body I0, as best shown in Fig. 5, each bore communicating with the outlet passage I4 and with one of the auxiliary passages I5 and I6 through a bleed opening |03, as best shown in Fig. 2 wherein one of the pressure regulating means is shown in detail, the other being identical thereto. A valve element |04 is adapted to seal the bleed opening |53, the valve element being disposed in a bore |05 in the head |06 of a plunger which is provided with a stem |08. The plunger head |06 is provided with a slot |09 therein which communicates with the outlet passage I4 and which communicates with the bleed opening |03 when the valve element |04 is unseated. The Valve element is normally held closed by a compressionspring I I I which encircles the plunger stem |08 and which is disposed in a bore |I2 in a plug member II3, the plug member being threadedly disposed in the bore |02 and being provided with an annular groove I4 therein for a sealing element I I5. The position of the plug member I3 in the bore |02 may be varied to vary the force exerted by the spring III on the valve element |04. It will be apparent that whenever the pressure in the auxiliary passage I5 (or in the auxiliary passage I6) exceeds a value which is determined by the force exerted by the spring III, the valve element |04 will be unseated to release suicient fluid to reduce the pressure to the desired value.

It will be apparent that the valve members I9 and 20 are hydraulically balanced internally since all openings therein are so formed that fluid therein exerts equal forces in both directions, each increment of area being complemented by an area increment of the same size. The valve members I9 and 20 are also hydraulically balanced externally if the fluid pressure in the valve chambers II and I2 adjacent the outlet passage I4 is equal to atmospheric pressure, each of the caps 38 being provided with an opening I6 therethrough to vent the opposite ends of the valve chambers to atmospheric pressure. The openings I I6 also serve as bleeds to release any fluid which may leak past the sealing elements 03. If the pressure in the valve chambers II and I2 adjacent the outlet port I5 is other than atmospheric, it will be apparent that the valve members IB and 20 may be balanced externally by providing for fluid communication between the opposite ends of the valve chambers.

Referring particularly to Figs. 2 and 3, it should be noted that the annular sealing element 64 provides a fluid-tight seal between the ports 45 and 52 through the liner 33 when the valve member I9 is in either of the operating positions illustrated. It will be apparent that when the valve member I9 is displaced from the operating position illustrated in Fig. 2 to the position illustrated in Fig. 3, the ports 68 must move past the sealing element 64. Since the sealing element 64 is preferably formed of a flexible and resilient material such as rubber or the like, the construction of the sealing element G4 and the annular groove 63 therefor must be designed so that the ports 68 slide past the sealing element in such a manner that the edges of the ports do not damage the sealing element.

The construction and opera-tion of the sealing element 64 are best shown in detail in the enlarged sectional views of Figs. '7 to 9, inclusive.

Referring particularly to Fig. '7, it will be noted that the sealingr element 64, which is preferably of circular cross section, normally engages the side walls II8 of the annular groove 63 in the liner 33 and may engage the base wall I I0 thereof, the relative dimensions of the sealing element and groove being such that portions of the sealing element are normally spaced from adjacent portions of the base and side walls of the groove. The sealing element 54 also engages the surface of the valve member I9 to provide a fluid-tight seal between the valve member I9 and liner 33, the pressure exerted by the fluid in the port 68|acting in the direction indicated by the arrow I2 As the valve member I0 is displaced in the direction of the arrow |22 so that the port E8 is opposite the sealing element 04 as shown in Fig. 8, the pressure exerted by the fluid acts in the direction indicated by the arrows |23 to deform the sealing element and compress it into the groove 63, the sealing element being deformed and compressed into the spaces existing between the normally undeformed sealing element and the base and side walls of the groove. Thus, the sealing element 04 disengages portions of the surface of the valve member I9 adjacent the port 68 so that the port may move past the sealing element without having the sealing element contact the edges of the port, thereby preventing chewing or tearing of the sealing element by the port edges. As the valve member I9 is displaced into the position shown in Fig. 9, the port 68 moves completely past the sealing element 5@ and the latter assumes its original, Linde-formed configuration so that the sealing element reengages the surface of the valve member I9 to provide a duid-tight seal between the ports lit and 52, the pressure exerted by the fluid in the port E8 now acting in the direction of the arrow |24. The sealing element 6A is compressed and clears the port 68 in a similar manner when the valve member i9 is displaced in the direction opposite to that indicated by the arrow 122. The sealing element 62 also operates in a similar manner with respect to the port 53. This feature of my invention thus permits the use of sealing elements of rubber or similar materials to provide a iiuidtight seal adjacent ports in a member while preventing damage to the sealing elements by the port edges whenever the sealing elements are displaced across the ports.

Although I have described an exemplary ernbodiment of my invention and have suggested a particular application thereof, I do not intend to be limited to the specific disclosures contained hereinsince the invention is susceptible to various other applications, and since various changes, modications, and substitutions may be incorporated in the embodiment disclosed without departing from the spirit of the invention. I hereby reserve the right, therefore, to all such changes, modifications, and substitutions, and to all such applications of my invention as properly come Within the scope of my appended claims.

I claim as my invention;

1. In a selector valve, the combination of: a pair of valve chambers respectively providing axes which are disposed in a common plane; inlet passage means communicating with said valve chambers; outlet passage means communicating with said valve chambers; a pair of auxiliary passage means respectively communicating with said valve chambers; valve means for providing fluid communication between said inlet passage means and one of said auxiliary passage means and between the other of said auxiliary passage means and said outlet passage means, said valve means including a pair of valve members which are reciprocable in the respective valve chambers; and actuating means rotatable about an axis parallel to said plane for moving said valve members in opposite directions in the respective valve chambers.

2. In a valve, the combination of: a valve chamber provided with first, second and third ports; and a piston-like valve member movable in said valve chamber between first and second positions, said valve member being provided with a passage therethrough which connects said rst and second ports when said member is in said first position, and an end of said valve member .being adapted to uncover Vsaid second and third ports when said member is in said second position to provide uid communication between said second and third ports.

RODNEY B. CAMPBELL.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 331,739 Harvey Dec. 8, 1885 2,010,329 Speth Aug. 6, 1935 2,101,025 Hunt Deo. 7, 1937 2,360,839 Bartsdale Oct. 24, 1944 2,365,748 Curtis Dec. 26, 1944 2,414,451 Christensen Jan. 21, 1947 FOREIGN PATENTS Number Country Date 12,913 Great Britain of 1905 

